1. Technical Field
The present invention relates to a printing apparatus including nozzles for discharging a dye ink and nozzles for discharging a pigment ink with the same color as the dye ink and a method of controlling the printing apparatus.
2. Related Art
As a printing apparatus including nozzles for discharging a dye ink and nozzles for discharging a pigment ink with the same color as the dye ink, an ink jet recording apparatus including nozzles for discharging a black dye ink for printing a high-quality color image on exclusive paper and nozzle for discharging particularly black pigment ink for clearly printing characters or the like on plain paper is known (for example, see JP-A-2000-225719). Such an ink jet recording apparatus includes a head in which a nozzle array for discharging a dye ink and a nozzle array for discharging a pigment ink are arranged in a direction crossing a transport direction of a medium, and may perform printing using the dye ink and the pigment ink at a predetermined position of the medium while moving the head in the crossing direction.
However, the dye ink and the pigment ink used in the ink jet recording apparatus may be different in concentration when the inks are discharged on the medium, even in the same black. In addition, when the dye ink and the pigment ink are discharged while reciprocally moving the head in the direction crossing the transport direction of the medium so as to form an image, the order of inks discharged at a predetermined position of the medium is reversed in forward and backward paths of the head. That is, for example, the pigment ink is discharged on the dye ink discharged on the medium in the forward path and the dye ink is discharged on the pigment ink discharged on the medium in the backward direction. When the order of discharged inks is reversed, a portion printed in the forward path and a portion printed in the backward path are different in concentration and thus unevenness or a stripe pattern occurs in an image. Therefore, image quality deteriorates.